Native Americans comprise a heterogeneous minority group that is increasingly vulnerable to the AIDS epidemic. The Navajo Nation is the largest Native American tribe. They confront elevated HIV risks due to developmental, geographic, economic and socio-cultural factors. Included in the latter are early initiation of sexual behavior, reproduction and heavy use of alcohol and other drugs (AOD). Primary prevention programs should be developed and evaluated to diminish the future incidence of HIV infection among Navajos and to promote behaviors during adolescence which reduce their HIV and AOD abuse risks. The proposed collaborative research project will develop, implement, and evaluate culturally relevant AIDS/AOD abuse prevention programs for Navajo youth and their families living on or near the Navajo Nation Reservation. It will integrate HIV/AIDS and AOD abuse prevention approaches with pre- existing communication practices in education, health, and community life. To improve its relevance for Navajos, the project has been designed with two phases. Phase #1 involves: (a) intensive anthropologic/market research program development prior to pilot testing in order to adapt the high school curriculum to Navajo contexts, and (b) similar development activities for a supporting program of communication media interventions which educate, motivate, and reinforce self-protective attitudes and behaviors towards AIDS and the misuse of alcohol and drugs among Navajo youth and their families. Phase #2 then entails: (c) modest scale replications and follow-up of the enhanced school-based interventions, (d) continuing systematic development, application and evaluation of the communication media intervention approaches to Navajo families, and (e) dissemination of the project's findings with its integrated HIV/AOD prevention programs. The school based study is conducted as a series of quasi-experiments with lagged interventions at five comparison sites serving Navajo youth: 2 small and 1 large on-reservation BIA affiliated schools and two BIA Dorms in towns bordering the reservation. During Phase II, approximately 1,050 ninth graders will receive the AIDS/AOD abuse interventions with pre-post assessments, boosters, & annual followups.